This invention relates generally to dispensing devices and more particularly to a device for controllably dispensing and volatilizing liquid by the user sucking or drawing on the device.
U.S. Pat. No. 4,993,436 was issued to this inventor on Feb. 19, 1991 for a hand-held dispensing and volatilizing device with reciprocal on/off control of air and liquid flows. Specifically, when a user blocks the device""s solitary air vent passage, the user can draw liquid from a reservoir by sucking. In contrast, when the solitary vent passage is unblocked, sucking draws air through the passage while drawing very little, if any, liquid from the reservoir. Further, in order to block the solitary air vent passage it is necessary for a user to cover the passage, for example with a finger.
The aforesaid control mechanism is somewhat crude. Consequently, a need yet remains for a hand-held aspirating and volatilizing device with a more a more refined and variable control of both air and liquid flows.
Briefly described, the present invention comprises a flexible sipping straw that a) has a solid plug inserted at the end of the straw which is farther from the straw""s flexible, pleated portion, b) has a porous plug inserted immediately above the flexible, pleated portion toward the solidly plugged end of the straw, and c) has a row of holes punched one per pleat in the trough of each pleat of the flexible portion of the straw. Thus, on one hand when all of the pleats are closed, the user can draw no air, but only liquid from the straw. On the other hand, as the user opens successive pleats, the ratio of air to liquid increases that the user can draw by sucking on the open end of the straw.
In a first preferred embodiment, the aperture and mechanical means of controlling the surface area of the aperture comprise a pleated section of the tube, wherein each pleat within the pleated section has both a crest and a trough, and wherein holes of suitable diameter are positioned in the trough of at least one of the pleats so that the ratio of air to liquid that may be drawn by a user sucking on the open end of said tube will depend directly on the number of pleats with holes in their troughs that are pulled open at any given time.
In a second preferred embodiment, the aperture comprises an opening such as an elongate slit or a series of holes and the mechanical means of controlling the surface area of said aperture comprises a partially open sleeve that encloses the aperture, which sleeve may be rotated about the cylindrical axis of the tubular body of the device so as to cover or uncover all or a portion of said aperture.
In a third preferred embodiment, the aperture comprises an opening such as an elongate slit or a series of holes, and the mechanical means of controlling the surface area of said aperture comprises either an external sleeve or an insert into the open end of the tubular body of the device, which sleeve or insert may be translated with respect to the cylindrical axis of the tubular body of the device so as to cover or uncover all or a portion of said aperture.
In operation, when the aperture is closed, the user can draw no air and only liquid from said tube by sucking on the open end of said tube. The amount of liquid that a user can draw out by sucking continuously at any one time is limited, however, by the fact that, in the absence of back-drafting of air through the porous plug into the reservoir, a vacuum develops in the reservoir as liquid is drawn out such that a single charge is created.
On the other hand, as the user opens or uncovers more and more of the aperture, the ratio of air to liquid increases that the user can draw by sucking on the open end of the tube. If the aperture is completely open then very little liquid, if any, may be drawn out of the reservoir. Nevertheless, volatilization of residual droplets of liquid that remain in the tube between the porous plug and the open end of the tube may create the sensation flavor even when no liquid is being drawn through the porous plug.